Well, Kaz, the shape is known as Melon Rib. They seem to have been made in many places. Crown Crystal of Australia definitely made some, as did a dutch company, but yours are neither.

On the shelves behind me, I four little mysteries exactly matching your vases. The interesting thing about these vases is that they seem to be very finely cased with the thickest layer white glass, then a thin layer of splotches and finally a very thin layer of white glass on the inside. I'm guessing it was probably made in the reverse way, starting with a blob of white glass, rolled in chips to make the splatters, then cased in clear glass, and finally blown into the mould. As to where they originated, I wish I knew.

That's the extent of my knowledge; hopefully someone will unearth something more at some stage.